/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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 *

 */

/*

 *

 * (C) Copyright IBM Corp. 1998-2010 - All Rights Reserved

 *

 */

#ifndef __HANGULAYOUTENGINE_H

#define __HANGULAYOUTENGINE_H

#include "LETypes.h"

#include "LEFontInstance.h"

#include "LEGlyphFilter.h"

#include "LayoutEngine.h"

#include "OpenTypeLayoutEngine.h"

#include "GlyphSubstitutionTables.h"

#include "GlyphDefinitionTables.h"

#include "GlyphPositioningTables.h"

U_NAMESPACE_BEGIN

class MPreFixups;

class LEGlyphStorage;

/**

 * This class implements OpenType layout for Old Hangul OpenType fonts, as

 * specified by Microsoft in "Creating and Supporting OpenType Fonts for

 * The Korean Hangul Script" (http://www.microsoft.com/typography/otfntdev/hangulot/default.htm)

 *

 * This class overrides the characterProcessing method to do Hangul character processing.

 * (See the MS spec. for more details)

 *

 * @internal

 */

class HangulOpenTypeLayoutEngine : public OpenTypeLayoutEngine

{

public:

    /**

     * This is the main constructor. It constructs an instance of HangulOpenTypeLayoutEngine for

     * a particular font, script and language. It takes the GSUB table as a parameter since

     * LayoutEngine::layoutEngineFactory has to read the GSUB table to know that it has an

     * Hangul OpenType font.

     *

     * @param fontInstance - the font

     * @param scriptCode - the script

     * @param langaugeCode - the language

     * @param gsubTable - the GSUB table

     * @param success - set to an error code if the operation fails

     *

     * @see LayoutEngine::layoutEngineFactory

     * @see OpenTypeLayoutEngine

     * @see ScriptAndLangaugeTags.h for script and language codes

     *

     * @internal

     */

    HangulOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode,

                               le_int32 typoFlags, const LEReferenceTo<GlyphSubstitutionTableHeader> &gsubTable, LEErrorCode &success);

    /**

     * This constructor is used when the font requires a "canned" GSUB table which can't be known

     * until after this constructor has been invoked.

     *

     * @param fontInstance - the font

     * @param scriptCode - the script

     * @param langaugeCode - the language

     * @param success - set to an error code if the operation fails

     *

     * @see OpenTypeLayoutEngine

     * @see ScriptAndLangaugeTags.h for script and language codes

     *

     * @internal

     */

    HangulOpenTypeLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode,

                              le_int32 typoFlags, LEErrorCode &success);

    /**

     * The destructor, virtual for correct polymorphic invocation.

     *

     * @internal

     */

   virtual ~HangulOpenTypeLayoutEngine();

    /**

     * ICU "poor man's RTTI", returns a UClassID for the actual class.

     *

     * @stable ICU 2.8

     */

    virtual UClassID getDynamicClassID() const;

    /**

     * ICU "poor man's RTTI", returns a UClassID for this class.

     *

     * @stable ICU 2.8

     */

    static UClassID getStaticClassID();

protected:

    /**

     * This method does Hangul OpenType character processing. It assigns the OpenType feature

     * tags to the characters, and may compose a character sequence into a modern Hangul syllable,

     * or decompose a modern Hangul syllable if it forms part of an old Hangul syllable.

     *

     * Input parameters:

     * @param chars - the input character context

     * @param offset - the index of the first character to process

     * @param count - the number of characters to process

     * @param max - the number of characters in the input context

     * @param rightToLeft - <code>TRUE</code> if the characters are in a right to left directional run

     * @param glyphStorage - the glyph storage object. The glyph and character index arrays will be set.

     *                       the auxillary data array will be set to the feature tags.

     *

     * Output parameters:

     * @param success - set to an error code if the operation fails

     *

     * @return the output character count

     *

     * @internal

     */

    virtual le_int32 characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,

            LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success);

};

U_NAMESPACE_END

#endif